1. Field of the Invention
This invention relates to contraceptive compositions and in particular to a contraceptive composition which includes biologically-active alpha-lactalbumin.
2. Description of the Prior Art
The search for effective contraceptives has been going on for literally thousands of years. Among the contraceptive methods presently in general use are oral contraceptives, intrauterine devices, diaphragms, condoms and various vaginal spermicides administered in the form of jellies, creams, foams, foaming tablets, suppositories and soluble films. As is commonly known, each of these contraceptive methods has disadvantages for particular individuals or for all individuals when used over an extended period of time. For example, the use of oral contraceptives, the most popular form of contraceptive at the present time, has been associated with nausea, depression, weight gain and headache, as well as an increased long-term risk of stroke, myocardial infarction, thromboembolia and hypertension.
In particular, the vaginal spermicides have come under increasing criticism because of the absorption and subsequent effects of the chemicals used in such preparations on various female tissues and organs. The spermicide most commonly used today in such preparations is the nonionic detergent nonylphenoxypolyethyleneoxyethanol (nonoxynol 9). Numerous studies have been done on the absorption of nonoxynol 9 by the vaginal epithelium. See, for example, Buttar, H. S., "Transvaginal Absorption and Disposition of Nonoxynol-9 in Gravid Rats", Toxicology Letters, Vol. 13, 1982, pages 211-216; Chvapil, M., Droegemueller, W., Owen, J. A., Eskelson, C. D., Betts, K., "Studies of Nonoxynol-9. I. The Effect on the Vaginas of Rabbits and Rats", Fertility and Sterility, Vol. 33, No. 4, April 1980, pages 445-449; Chvapil, M., Eskelson, C. D., Droegemueller, W., Ulreich, J. B., Owen, J. A., Ludwig, J. C., Stiffel, V. M., "New Data on the Pharmacokinetics of Nonoxynol 9", in Vaginal Contraception: New Developments, Zatuchni et al. editors, Harper & Row, Hagerstown, Md., 1979, pages 165-174; Chvapil, M., Eskelson, C. D., Stiffel, V., Owen, J. S., and Droegemueller, W., "Studies on Nonoxynol-9. II. Intravaginal Absorption, Distribution, Metabolism and Excretion in Rats and Rabbits", Contraception, September 1980, Vol. 22, No. 3, pages 325-339; Jick, H., Walker, A. M., Rothman, K. J., Hunter, J. R., Holmes, L. B., Watkins, R. N., D'Eward, D. C., Danford, A., Madsen, S., "Vaginal Spermicides and Congenital Disorders", JAMA, Apr. 3, 1981, Vol. 245, No. 13, pages 1329-1332; and Shapiro, S., Slone, D., Holnonon, O. P., Kaufman, D. W., Rosenberg, L., Mitchell, A. A., Helmrich, S. P., "Birth Defects and Vaginal Spermicides", JAMA, May 7, 1982, Vol. 247, No. 17, pages 2381-2384.
Although the results of these studies are not without controversy, there seems to be general agreement that nonoxynol 9 is rapidly taken up by the vaginal epithelium, enters the circulation, and accumulates in the liver, among other tissues. Biochemical and morphological studies have documented abnormalities in these tissues as a result of nonoxynol 9 administration. Moreover, the detergent can be found in the milk of lactating rats and in the serum of their pups within two hours after an intravaginal application. Further, although very controversial, some studies have suggested an association of congenital abnormalities with the use of nonoxynol 9 as a spermicidal agent. See "Vaginal Spermicides and Congenital Disorders" and "Birth Defects and Vaginal Spermicides", supra.